1) Field of the Invention
This application is in the field of storm water pollution prevention and regulatory compliance with new storm water requirements. The invention is targeted towards a multiple stage treatment of storm water contaminants for the removal of dissolved and liquid phase storm water contaminants through the use of absorbent socks as the primary treatment method and removal of particulate matter or other contaminants through the use of semi-permeable bags, which may be treated with special resins to retain such contaminants as soaps or nitrates, at the openings to storm water catch basins. The structure, sock and bags are located on the peripheral edge of the storm sewer catch basins which enables storm water to flow freely without encumbering the storm water flow nor the purpose of the storm sewer system.
2) Description of the Prior Art
Storm water collection and conveyance systems are well known and in widespread use to provide flood control and proper drainage. Numerous inventions in the field of storm water sewers and pollution prevention have been patented over the last century which can modify storm sewer catch basins to prevent pollution from discharging out of the storm sewer or provide a support mechanism for storm sewer catch basins.
U.S. Patent Documents
______________________________________ U.S. Pat. Nos. 1,310,055 07/1919 Caldwell 4,419,232 12/1983 Amtyr, et. al. 210/164 5,383,745 01/1995 Shannon 210/164 5,632,888 05/1997 Chinn, et. al. 210/164 797,585 08/1905 Kees 4,174,183 11/1979 Ferns 404/26 4,188,151 02/1980 Hall 404/26 5,632,889 05/1997 Tharp 210/165 5,720,574 02/1998 Barella 405/52 Foreign Patent Documents 1,275,277 05/1972 UK Flegel 210/165 114,257 06/1945 Sweden Mattisson 210/164 ______________________________________
Caldwell (U.S. Pat. No. 1,310,055) developed a storm water treatment device, which was simply a strainer for catching large debris such as sticks, mud and leaves and allowing them to be broken up by storm water flows or removed from the system.
This device is ineffective, and indeed not intended to, remove fine particulate matter, dissolved and liquid phase contaminants. In fact, coarse material was intended to be broken up and enter the storm sewer system to prevent plugging of storm sewers, rather than being removed from the system. The technology employed is physical separation through straining. Furthermore, the device is located at the center of the storm sewer opening thus obstructing flow and does not employ similar treatment technology.
Amtyr, et.al. (U.S. Pat. No. 4,419,232) developed a two stage filtering and collection device for water drains. The first stage was a course strainer to remove wooden pegs and large objects, while the second stage was a fine mesh filtering bag, which had a primary purpose of removing finer particulate matter Such as sand and having limited capabilities of filtering out oils and other liquids to a certain extent. Furthermore, the device is located at the center of the storm sewer opening thus obstructing flow and does not employ similar treatment technology.
The disadvantage with this design is that dissolved impurities are not removed and liquid phase impurities are ineffectively removed by this filtration process. Furthermore, what liquid phase impurities and finer particulate matter removed by the filtering bag would be re-suspended during high flow conditions and either flow into the storm sewer system or back up and flood the drainage area. In fact, high storm water flows and water pressures would likely tear or otherwise destroy the filter bag. This design would severely limit storm water flow rates.
Shannon (U.S. Pat. No. 5,383,745) developed a Hazardous Materials Catch Basin, which does not treat storm water, but seals off hazardous materials from entering a storm sewer system. Spill containment catch basins are intended to contain a specific contaminant usually stored in bulk quantities at the site and is not intended to treat storm water pollution, but prevent the release of a spill material to the storm sewer. The spill containment catch basin specifically restricts or totally stops the flow of liquids in order to prevent the release of the contaminant of concern. These spill containment manholes are often inside buildings with bulk storage or specifically designed outside as spill containment units with little drainage area such that the diversion of storm water is not the primary concern of the unit. Furthermore, the device is located at the center of the storm sewer opening and requires fasteners and mechanical action to stop flows.
The disadvantage of this design is that storm water flows are severely restricted due to plugging with solids or the purposeful action of the unit to stop flows. Furthermore, only a specific contaminant is being targeted and the device is not intended to treat the liquid and dissolved phase contaminants in storm water. The device requires complex installation with fasteners and mechanical components.
Chinn, et. al. (U.S. Pat. No. 5,632,888 developed an environmental filter, which claims to remove solids by filtration by allowing water to run through a fabric type material over the opening. The aforementioned device is located centrally thus obstructing flow and does not employ similar treatment technology. Furthermore, the unit is located above the storm sewer opening and represents a slip, trip or fall hazard.
Kees (U.S. Pat. No. 797,585) developed a device, which was a tight fitting, water tight cover that could be converted to a ventilated cover to allow air exchange so that basements could be aired thoroughly. There is no provision for storm water pollution prevention claimed. Furthermore, the device is located at the center of the storm sewer opening.
Fems (U.S. Pat. No. 4,174,183) developed a device, which is a support frame for manhole covers and similar articles of highway furniture. There is no provision for storm water pollution prevention claimed. Furthermore, the device is located on the peripheral edge of the opening yet is intended to support highway furniture located at the center of the storm sewer opening.
Hall (U.S. Pat. No. 4,188,151) developed a device, which extends a manhole up such that when new asphalt, concrete or the surroundings are otherwise raised, the manhole can be raised such that it is level with the ground, road, or other surroundings and not beneath it. There is no provision for storm water pollution prevention claimed. Furthermore, the device is located on the peripheral edge of the opening yet is intended to support highway furniture located at the center of the storm sewer opening.
Tharp (U.S. Pat. No. 5,632,889) developed a device, which sits on the peripheral edge of a manhole to hold a specific environmental product; an absorbent filter media, in which water filters down through a perforated bottom such that water contacts the absorbent and hydrocarbons are selectively removed.
This device does not have the option of removing fine particulate matter and requires a deep trough to ensure contact with the absorbent as the flow of the storm water is down through the absorbent.
Barella (U.S. Pat. No. 5,720,574) developed a device, which sits on the peripheral edge of a manhole to hold a specific environmental product; an absorbent filter media, in which water filters down through a perforated bottom such that water contacts the absorbent and hydrocarbons are selectively removed.
This device does not have the option of removing fine particulate matter and requires a deep trough to ensure contact with the absorbent as the flow of the storm water is down through the absorbent.
Flegel--UK (Patent # 1,275,277) developed a device, which is interlocking framing and grating for trench drains. There is no provision for storm water pollution prevention claimed. Furthermore, the device is located at the center of the storm sewer opening.
Mattisson--Sweden (Patent # 114,257) developed a device, which is a frame for catch basins. There is no provision for storm water pollution prevention claimed. Furthermore, the apparatus is located on the peripheral edge of the opening yet is intended to support highway furniture located at the center of the storm sewer opening.
No prior inventions can treat the wide spectrum of storm water contaminants while ensuring that storm water drainage is maintained at the flows intended for in drainage designs. My invention is designed to employ absorbent technology by holding an absorbent sock only on the peripheral edge of the unit to remove liquid and dissolved contaminants and bags located between the troughs on the peripheral edge to collect particulate matter. No prior invention noted above or known to the Applicant employees both treatment technologies within the storm sewer catch basin opening. Furthermore, the prior art can not be easily adapted to hold sample bottles wherein sampling of storm water is now required as part of storm water permits nor do any of the prior inventions hold bags on the peripheral edge to the storm sewer opening.
Furthermore, there are devices noted above (Tharp and Barella) that hold absorbents on the peripheral edge of the storm sewer, but employ a perforated bottom such that storm water flows through the device. While my invention have a plurality of troughs that are impermeable to water and use the perimeter of the storm sewer to provide contact time with the absorbent material. Hence, the contact time with the absorbent sock with my invention would approximate the same removal efficiency as a device with a single trough and a perforated bottom that is much deeper. This alleviates the problems associated with installing a deeper trough involving obstructions within the catch basins or depth of the catch basin. Another problem associated with Tharp and Barella is that the one trough system filled with absorbent limits the amount of water that can contact the absorbent material as the porosity of the absorbent material and size of the perforations in their device would severely restrict flow, whereas my invention having a plurality of troughs and openings can accommodate much higher flow rates through the troughs and much more water would contact the absorbent material.
My invention being located at the top of the catch basin opening near the peripheral edge alleviates a major problem associated with other designs which are set further inside or are deeper involving removal and replacement of absorbents and bags. Ergonomics and safety considerations favor the bags and absorbent being located inches from the surface on the peripheral edge alleviating the need for reaching as far down or over in my invention versus these other designs.
Neither the Tharp (U.S. Pat. No. 5,632.889), Barella (U.S. Pat. No. 5,720,574) nor Amrtyr et. al. (U.S. Pat. No. 4,419,232) is adaptable to holding a bag on the outside edge of the storm sewer catch basin as the entire periphery of the catch basin is occupied by the apparatus. Additionally, the placing of a bag on the outside edge reduces the stresses and forces on the bag such that tearing and destruction of the bag will not occur and water can flow freely through the unoccupied center portion. The bags in my invention would also be much lighter than the bag in the Amtyr invention as the openings are much smaller and the capacity of the bags could be much less than one bag extending over the entire opening.